1. Field of the Invention
This invention relates to a packing film stretching and rewinding machine, particularly to one able to carry out stretching, lip-folding, swinging and re-winding for a packing film on a machine table at the same time. The packing film stretching and rewinding machine is provided with a stretching device for stretching, lengthening and thinning the packing film, and after stretched, the packing film has opposite edges folded by a lip-folding device to enhance the strength of the opposite edges of the packing film. After edge folding, the packing film can be quickly re-wound into small rolls by means of a swing device and a re-winding device. Thus, when the stretched packing film is rewound into small rolls, the portion of a reel located at the opposite edges of the packing film will not be tightened and deformed, and it is needless to stop operation of the machine in the course of whole operation, able to have the packing film stretched, lip folded and rewound into small rolls quickly, greatly increasing output, saving man power and the placing space for the machine table, reducing waste materials and lowering producing cost.
2. Description of the Prior Art
Generally, a packing film with a comparatively great thickness to be used for packing articles is manufactured by a packing film manufacturing machine and the packing film is usually wound into a large roll. Substantially, a common packing film manufacturing machine cannot manufacture a very thin packing film; therefore, the packing film manufactured has to be stretched and thinned by a stretching machine so that it can be used for packing articles conveniently. After stretched, the packing film is first wound into a large roll and then this large roll of stretched packing film is manually moved onto a rewinding machine to be rewound into lots of small rolls of packing film by means of paper reels. However, after the conventional packing film is stretched, the stretching machine has to be stopped operating before the stretched packing film is moved onto a re-winding machine to be rewound. As mentioned above, after each large roll of packing film is stretched, the stretching machine must be stopped operating and the large roll of packing film has to be moved onto the rewinding machine, thus taking lots of time and exertion. Further, a common rewinding machine can rewind only one roll of packing film at one time, with the action of rewinding complicated and slow, resulting in limited output of stretched and rewound packing films. Furthermore, after the packing film is stretched by the stretching machine, the opposite edges of the packing film will become thicker than the rest portion of the packing film; therefore, when the packing film is orderly rewound into small rolls, the thicker opposite edges of the packing film will produce a tightening force to the reel of the packing film and make the reel deformed. In addition, although the opposite edges of the packing film are thicker than the rest portion of the packing film, when the packing film is packed on an article and pulled forcefully, the opposite edges of the packing film are easy to be broken by pulling. Thus, the packing film fails to be completely packed on the article and the broken part of the packing film has to be torn off, squandering away the packing film. Moreover, there must be a large space for placing the stretching machine, the re-winding machine and other related machines at the same time.